Siah, the Moonsire

At the beginning of each opponent's upkeep,
Siah deals damage to that player equal to twice
the number of permanents you control that
player owns.
{t}, Sacrifice two other permanents that share a
card type: Gain control of target permanent that
shares a card type with the sacrificed permanents.
"I do what is necesary to survive, no matter
how cruel it may seem."